In-situ inspection system for electron beam additive manufacturing based on phase measurement profilometry
Effective in-situ inspection of the powder bed and the quality of the printed parts during the manufacturing process of Electron Beam Additive Manufacturing (EBAM) is essential for improvement of its manufacturing process and to enhance product quality. EBAM in-situ inspection during the manufacturing process has two phases. The first phase is to inspect the state of the rough powder bed and assess the powder delivery. The second phase is to inspect rough powder bed and the reflective metal surface at the same time which has high dynamic range measurement issues. This talk presents a novel intelligent fringe projection technique using support-vector-machine (SVM) algorithm to measure the 3D topography of high dynamic range surface on a layer-by-layer basis within the EBAM machine. To facilitate the SVM implementation a range of EBAM manufactured surfaces are utilised as samples for training and classification. The training measurement are based on different exposure times and saturated pixels are utilised as feature vectors to predict tested samples categories. Training errors are evaluated, and the correct recognition rate is 91%, which indicates the proposed training method can effectively predict the categories of the surfaces.
Dr F. Gao is a Reader of Metrology and Instrumentation at the School of Computing and Engineering, University of Huddersfield, UK. His research interests focus on the study of optical interferometry, 3D fringe projection for surface measurement, metasurfaces and their applications. He studied precision measurement and instrumentation as an undergraduate and postgraduate student at Tianjin University. He was awarded a Ph.D. degree for “Development of a novel multi-Function Tribological Nano-Probe Microscope” at Coventry University. His academic experience includes work in the research and development of dimensional metrology instruments and measurement standards at the National Institute of Metrology of China and PTB, Germany; as well as research in the fields of surface measurement and surface strain measurement at Loughborough University, UK.
Personal homepage: https://pure.hud.ac.uk/en/persons/feng-gao